"NFL Total Access" continues with its "32 teams in 32 days" series. We decided to score some brownie points by writing an accompanying post each night. We'll focus on one goal that each team needs to accomplish before Week 1.

Warren Sapp (playing to character) ruffled feathers last season when he tagged the Pittsburgh Steelers' defense as old, slow and on the way out. That war cry was premature.

The Steelers finished with the league's top unit -- easy to forget after the disaster flick we witnessed in Denver.

Tim Tebow, of all souls, fried Pittsburgh in an AFC wild-card overtime thriller, sending the Steelers home as a confused bunch.

Brooks: Haley's impact on Pittsburgh

Some questioned Pittsburgh's hiring of Todd
Haley to run the offense, but
Bucky Brooks thinks it's a perfect match.
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The offseason has brought change: Aaron Smith has retired; James Farrior is out the door, and cornerback William Gay won't be back in 2012. Many of the Steelers veterans are aging (Brett Keisel and his flowing beard are 33; James Harrison -- still terrifying -- is 34). This remains one of the NFL's best defenses, but the time is now for youth to fill in the gaps for coordinator Dick LeBeau.

Who's under the microscope? Let's start here:

1. Cameron Heyward: The Steelers have taught proper 3-4 defense to the rest of the league for years. Versatile play from your down linemen is key to this scheme and Heyward is a building block at defensive end. He's an intriguing physical prospect, but didn't start a game last in 2011 after being slowed by offseason surgery. He wasn't asked to carry much weight as a rookie, but the training wheels are off.

2. Ziggy Hood: Another former first-round pick along the defensive line, Hood is Heyward's key competition to fill the void left by Aaron Smith. Hood also plays inside, but Casey Hampton (another 30-something) remains penciled in at nose tackle, if he can stay healthy. Hood shed pounds and gained muscle this offseason, and remains an intriguing pass rusher.

3. The young defensive backfield: Teams are using three-plus DBs throughout games, especially against a weapon-rich team like the New England Patriots. Pittsburgh has a crew of young cornerbacks ready to see an increased workload. Keenan Lewis is the likely starter across from Ike Taylor, but Cortez Allen could make his case in training camp. Curtis Brown will see the field in nickel situations. The trio must prove they belong in Pittsburgh.

Let's pump the brakes on the "old and slow" jokes, but for the Steelers to remain at the top, these younger players must emerge in 2012.